Development of an ABS Nanocomposite Material and Its Application to a Fire-Resistant Glazing System - Part I: Development of an ABS Nanocomposite Material

This study is focused on the development of a curtain-wall-type fire-resistant glazing system to contribute to both energy efficiency and fire safety of a building. The weakness of the aluminum frame on thermal insulation was supplemented by an ABS nanocomposite material with a superior thermal insulation performance. It contained (i) a maleic-anhydride-grafted ABS to improve the dispersion of clay, (ii) nanoscale clay, and (iii) intumescent material to retard the combustion on the exposed surface of the polymer. A series of X-ray diffraction, transmission electron microscopy, differential scanning calorimetry, LFA, and cone calorimetry tests were carried out to analyze the degree of improvement in flame retardancy and optimize the compound ratio. In Part II (the authors’ companion paper), the ABS nanocomposite material based on the optimized compound ratio was scaled up for application to a fire-resistant glazing system in industries. Bench- and full-scale tests were performed to confirm the system’s performances in terms of both thermal resistance and insulation.

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Development of an ABS Nanocomposite Material and Its Application to a Fire-Resistant Glazing System - Part II: Development of a Curtain-Wall-Type Fire-Resistant Glazing System

Fire science and engineering ◽

10.7731/kifse.b8a35e9a ◽

2020 ◽

Vol 34 (5) ◽

pp. 10-17

Author(s):

Sungwook Kang ◽

Minjae Kwon ◽

J. Yoon Choi ◽

Jae Wan Park

Keyword(s):

Heat Transfer Performance ◽

Companion Paper ◽

Nanocomposite Material ◽

Transfer Performance ◽

Curtain Wall ◽

System A ◽

Pilot Model ◽

System Part ◽

Scale Test ◽

Bench Scale Test

This study is focused on the development of a curtain-wall-type fire-resistant glazing system to contribute to both energy efficiency and fire safety of a building. The development of an ABS nanocomposite material and its improvement in flammability are presented in Part I (the authors’ companion paper). In this study, the ABS nanocomposite material was scaled up for application to a fire-resistant glazing system in industries. A bench-scale test was designed to quantitatively analyze the frame’s heat transfer performance. To manufacture a pilot model of the glazing system, a glazing part was designed based on numerical simulations of thermal insulation. The performance of the entire glazing system was tested on a full scale in terms of thermal resistance and insulation.

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Effects of Sintering Temperature on Densification, Microstructure and Mechanical Properties of Al-Based Alloy by High-Velocity Compaction

Metals ◽

10.3390/met11020218 ◽

2021 ◽

Vol 11 (2) ◽

pp. 218

Author(s):

Xianjie Yuan ◽

Xuanhui Qu ◽

Haiqing Yin ◽

Zaiqiang Feng ◽

Mingqi Tang ◽

...

Keyword(s):

Mechanical Properties ◽

High Velocity ◽

Sintered Density ◽

Sintering Temperature ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Transmission Electron ◽

High Velocity Compaction ◽

Sintered Temperature

This present work investigates the effects of sintering temperature on densification, mechanical properties and microstructure of Al-based alloy pressed by high-velocity compaction. The green samples were heated under the flow of high pure (99.99 wt%) N2. The heating rate was 4 °C/min before 315 °C. For reducing the residual stress, the samples were isothermally held for one h. Then, the specimens were respectively heated at the rate of 10 °C/min to the temperature between 540 °C and 700 °C, held for one h, and then furnace-cooled to the room temperature. Results indicate that when the sintered temperature was 640 °C, both the sintered density and mechanical properties was optimum. Differential Scanning Calorimetry, X-ray diffraction of sintered samples, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, and Transmission Electron Microscope were used to analyse the microstructure and phases.

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Preparation, characterization and scale-up of sesamol loaded solid lipid nanoparticles

Nanotechnology Development ◽

10.4081/nd.2012.e8 ◽

2012 ◽

Vol 2 (1) ◽

pp. 8 ◽

Cited By ~ 5

Author(s):

Vandita Kakkar ◽

Indu Pal Kaur

Keyword(s):

Solid Lipid Nanoparticles ◽

Scale Up ◽

Spherical Shape ◽

Entrapment Efficiency ◽

Lipid Nanoparticles ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Solid Lipid ◽

Transmission Electron ◽

The Brain

Sesamol loaded solid lipid nanoparticles (SSLNs) were prepared with the aim of minimizing its distribution to tissues and achieving its targeting to the brain. Three scale-up batches (100x1 L) of S-SLNs were prepared using a microemulsification technique and all parameters were statistically compared with the small batch (1x;10 mL). S-SLNs with a particle size of less than 106 nm with a spherical shape (transmission electron microscopy) were successfully prepared with a total drug content and entrapment efficiency of 94.26±2.71% and 72.57±5.20%, respectively. Differential scanning calorimetry and infrared spectroscopy confirmed the formation of lipidic nanoparticles while powder X-ray diffraction revealed their amorphous profile. S-SLNs were found to be stable for three months at 5±3°C in accordance with International Conference on Harmonisation guidelines. The SLN preparation process was successfully scaled-up to a 100x batch on a laboratory scale. The procedure was easy to perform and allowed reproducible SLN dispersions to be obtained.

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Role of Surfactants in the Properties of Poly(Ethylene Terephthalate)/Purified Clay Nanocomposites

Materials ◽

10.3390/ma11081397 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1397 ◽

Cited By ~ 2

Author(s):

Elaine dos Santos ◽

Marcus Fook ◽

Oscar Malta ◽

Suédina de Lima Silva ◽

Itamara Leite

Keyword(s):

Clay Nanocomposites ◽

Phosphonium Salts ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Transmission Electron ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene ◽

Alkyl Ammonium ◽

Pet Crystallization

Purified clay was modified with different amounts of alkyl ammonium and phosphonium salts and used as filler in the preparation of PET nanocomposites via melt intercalation. The effect of this type of filler on morphology and thermal and mechanical properties of PET nanocomposites was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analyses (TG), tensile properties, and transmission electron microscopy (TEM). The results showed that the mixture of alkyl ammonium and phosphonium salts favored the production of PET nanocomposites with intercalated and partially exfoliated morphologies with slight improvement in thermal stability. In addition, the incorporation of these organoclays tended to inhibit PET crystallization behavior, which is profitable in the production of transparent bottles.

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The Evaluation of Meloxicam Nanocrystals by Oral Administration with Different Particle Sizes

Molecules ◽

10.3390/molecules27020421 ◽

2022 ◽

Vol 27 (2) ◽

pp. 421

Author(s):

Yao Yu ◽

Yang Tian ◽

Hui Zhang ◽

Qingxian Jia ◽

Xuejun Chen ◽

...

Keyword(s):

Particle Size ◽

Water Solubility ◽

Cell Model ◽

Particle Sizes ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Laser Scattering ◽

Transport Studies ◽

Transmission Electron ◽

Transmission And Absorption

Meloxicam (MLX) is a non-steroidal anti-inflammatory drug used to treat rheumatoid arthritis and osteoarthritis. However, its poor water solubility limits the dissolution process and influences absorption. In order to solve this problem and improve its bioavailability, we prepared it in nanocrystals with three different particle sizes to improve solubility and compare the differences between various particle sizes. The nanocrystal particle sizes were studied through dynamic light scattering (DLS) and laser scattering (LS). Transmission electron microscopy (TEM) was used to characterize the morphology of nanocrystals. The sizes of meloxicam-nanocrystals-A (MLX-NCs-A), meloxicam-nanocrystals-B (MLX-NCs-B), and meloxicam-nanocrystals-C (MLX-NCs-C) were 3.262 ± 0.016 μm, 460.2 ± 9.5 nm, and 204.9 ± 2.8 nm, respectively. Molecular simulation was used to explore the distribution and interaction energy of MLX molecules and stabilizer molecules in water. The results of differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) proved that the crystalline state did not change in the preparation process. Transport studies of the Caco-2 cell model indicated that the cumulative degree of transport would increase as the particle size decreased. Additionally, plasma concentration–time curves showed that the AUC0–∞ of MLX-NCs-C were 3.58- and 2.92-fold greater than those of MLX-NCs-A and MLX-NCs-B, respectively. These results indicate that preparing MLX in nanocrystals can effectively improve the bioavailability, and the particle size of nanocrystals is an important factor in transmission and absorption.

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Characterization of the Phase Transformations in the Shape Memory Alloy Ni-36 at.% Al

MRS Proceedings ◽

10.1557/proc-246-61 ◽

1991 ◽

Vol 246 ◽

Cited By ~ 6

Author(s):

J.A. Horton ◽

E.P. George ◽

C.J. Sparks ◽

M.Y. Kao ◽

O.B. Cavin ◽

...

Keyword(s):

High Temperature ◽

Shape Memory ◽

Phase Transformations ◽

Hot Extrusion ◽

Exothermic Peak ◽

Nickel Aluminum ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Transmission Electron

AbstractA survey by differential scanning calorimetry (DSC) and recovery during heating of indentations on a series of nickel-aluminum alloys showed that the Ni-36 at.% Al composition has the best potential for a recoverable shape memory effect at temperatures above 100°C. The phase transformations were studied by high temperature transmission electron microscopy (TEM) and by high temperature x-ray diffraction (HTXRD). Quenching from 1200°C resulted in a single phase, fully martensitic structure. The initial quenched-in martensites were found by both TEM and X-ray diffraction to consist of primarily a body centered tetragonal (bct) phase with some body centered orthorhombic (bco) phase present. On the first heating cycle, DSC showed an endothermic peak at 121°C and an exothermic peak at 289°C, and upon cooling a martensite exothermic peak at 115° C. Upon subsequent cycles the 289°C peak disappeared. High temperature X-ray diffraction, with a heating rate of 2°C/min, showed the expected transformation of bct phase to B2 between 100 and 200°C, however the bco phase remained intact. At 400 to 450°C the B2 phase transformed to Ni2Al and Ni5Al3. During TEM heating experiments a dislocation-free martensite transformed reversibly to B2 at temperatures less than 150°C. At higher temperatures (nearly 600°C) 1/3, 1/3, 1/3 reflections from an ω-like phase formed. Upon cooling, the 1/3, 1/3, 1/3 reflections disappeared and a more complicated martensite resulted. Boron additions suppressed intergranular fracture and, as expected, resulted in no ductility improvements. Boron additions and/or hot extrusion encouraged the formation of a superordered bct structure with 1/2, 1/2, 0 reflections.

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Preparation and Property of Al87Ce3Ni8.5Mn1.5 Nanophase Amorphous Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.412.263 ◽

2011 ◽

Vol 412 ◽

pp. 263-266

Author(s):

Hong Wei Zhang ◽

Li Li Zhang ◽

Feng Rui Zhai ◽

Jia Jin Tian ◽

Can Bang Zhang

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Single Phase ◽

Volume Fraction ◽

Material Structure ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Transmission Electron ◽

Different Temperatures

The higher mechanical strength of Al87Ce3Ni8.5Mn1.5 nanophase amorphous composites has been obtained with two methods. The first nanophase amorphous composites are directly produced by the single roller spin quenching technology. The method taken for the second nanophase amorphous composites is at first to obtain amorphous single-phase alloy, followed by annealed at different temperatures .The formative condition, the microstructure, the particle size, the volume fraction of α-Al phase and microhardness of nanophase amorphous composites etc have been investigated and compared by X-ray diffraction (XRD) and transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The microstructure of composites produced by the second method is higher than the former, the fabricated material structure of the system is more uniform and the process is easier to control.

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Preparation, characterization, and properties of polystyrene/Na-montmorillonite composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705718785691 ◽

2018 ◽

Vol 32 (8) ◽

pp. 1078-1091 ◽

Cited By ~ 4

Author(s):

Sibel Erol Dağ ◽

Pınar Acar Bozkurt ◽

Fatma Eroğlu ◽

Meltem Çelik

Keyword(s):

Electron Microscopy ◽

Interlayer Spacing ◽

Decomposition Temperature ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Sem Images ◽

Specific Pore Volume ◽

Transmission Electron ◽

Thermal Stability Of

A series of polystyrene (PS)/unmodified Na-montmorillonite (Na-MMT) composites were prepared via in situ radical polymerization. The prepared composites were characterized using various techniques. The presence of various functional groups in the unmodified Na-MMT and PS/unmodified Na-MMT composite was confirmed by Fourier transform infrared spectroscopy. Morphology and particle size of prepared composites was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). According to the XRD and TEM results, the interlayer spacing of MMT layers was expanded. SEM images showed a spongy and porous-shaped morphology of composites. TEM revealed the Na-MMT intercalated in PS matrix. The thermal stability of PS/unmodified Na-MMT composites was significantly improved as compared to PS, which is confirmed using thermogravimetric analysis (TGA). The TGA curves indicated that the decomposition temperature of composites is higher at 24–51°C depending on the composition of the mixture than that of pure PS. The differential scanning calorimetry (DSC) results showed that the glass transition temperature of composites was higher as compared to PS. The moisture retention, water uptake, Brunauer–Emmett–Teller specific surface area, and specific pore volume of composites were also investigated. Water resistance of the composites can be greatly improved.

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Structure and Optical Properties of ZnO and ZnO2 Nanoparticles

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.56.49 ◽

2019 ◽

Vol 56 ◽

pp. 49-62 ◽

Cited By ~ 2

Author(s):

Javier Eliel Morales-Mendoza ◽

Francisco Paraguay-Delgado ◽

J.A. Duarte Moller ◽

Guillermo Herrera-Pérez ◽

Nicolaza Pariona

Keyword(s):

Heat Treatment ◽

Band Edge Emission ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Transmission Electron ◽

Colloidal Method ◽

Zinc Peroxide ◽

Average Size ◽

Thermal Stability Of ◽

Raman And Ir Spectroscopy

Zinc oxide (ZnO) and Zinc peroxide (ZnO2) nanoparticles were synthesized by colloidal method at low temperature. The thermal stability of ZnO2was studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-Ray diffraction (XRD). The crystalline structure and phase change from ZnO2to ZnO by heat treatment was studied in detail. Morphology and particle size was examined using Transmission Electron Microscopy (TEM), for as synthesized ZnO and ZnO2the shape of particles were cuasi-spherical for both materials with average size of 10±2.2 nm and 2.5±0.4 nm, respectively; The crystal size for ZnO obtained by heat treatment was 8±2.2 nm. Electron density contours show the chemical bond type ionic and covalent for ZnO and ZnO2. The vibrational properties were analyzed by Raman and IR spectroscopy. Band gap values were obtained from ultraviolet-visible (UV-Vis) absorbance spectrum. Photoluminescence (PL) spectrum for ZnO shows two emission edges located at 445 and 492 nm and in the case of ZnO2presents one edge at 364 nm originated from the band edge emission. The optical spectra present a hypsochromic shift, compared with some reported in the literature.

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The Effect of Nanosizing on the Oxidation of Partially Oxidized Copper Nanoparticles

Materials ◽

10.3390/ma13122878 ◽

2020 ◽

Vol 13 (12) ◽

pp. 2878

Author(s):

Jindřich Leitner ◽

David Sedmidubský ◽

Michal Lojka ◽

Ondřej Jankovský

Keyword(s):

Copper Nanoparticles ◽

Scanning Transmission Electron Microscopy ◽

Oxidation Mechanism ◽

Oxidation Reactions ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Final State ◽

Micro Particles ◽

Transmission Electron ◽

Scanning Transmission

Copper nanoparticles are of great interest in various applications, such as catalysis, cooling fluids, conductive inks or for their antibacterial activity. In this paper, the thermal behavior of copper nanoparticles was studied using thermogravimetry, differential thermal analysis and differential scanning calorimetry. Original Cu samples as well as the products of oxidation were analysed by X-ray diffraction, scanning/transmission electron microscopy and energy dispersive spectroscopy. A step-by-step oxidation mechanism during the oxidation of Cu nano-powders was observed. The Cu-nano oxidation starts slightly above 150 °C when bulk copper does not yet react. The dominant oxidation product in the first step is Cu2O while CuO was identified as the final state of oxidation. Our results confirm an easier oxidation process of Cu-nano than Cu-micro particles, which must be attributed to kinetic not thermodynamic aspects of oxidation reactions.

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